This notebook is around 3 years old. In the last few weeks the touchpad has started to behave erratically. The mouse pointer starts to jump about the page. I have tried i) uninstalling the driver for the mouse, and rebooting; and ii) manually updating with the latest driver version from HP. An external mouse connected by USB funtions correctly. The error code I get from the HP hardware test is: Mouse/Touchpad Pointer Test | RK2N3R-8JSA27-XD7X7F-G23013 | FAILED. The product number is X0Q75ES#ABU and the serial number is [edited]. Any suggestions of what to try next?